passProps is passed down, and you even get a navigation bar for free. (The navigation bar can be hidden by giving the route object a property of navigationBarHidden set to true.)

Navigator

If you've looked at the React Native documentation for the Navigator component, you'll find things aren't so simple. Navigator is given a renderScene prop which returns JSX to be rendered, in response to having a route pushed onto its stack. This is from the React Native documentation:

Now this will work in place of NavigatorIOS. One thing we need to address, however, is the lack of a navigation bar. You have to implement this on your own; I suggest creating a reusable Navbar component, like the following: